In July, the Italian anti-establishment, populist parties Five Star Movement (M5S) and Lega Nord relaxed a rule requiring children show a doctors note to prove they have been vaccinated before they can enroll in state run schools — parents only needed to assure the school the children had been immunised. In August, the requirement to vaccinate was dropped altogether.

What happens next will surprise you! No, not the flood of measles cases — that wouldn't surprise anyone. No, what happened is the anti-vaxxers changed their minds! They actually revoked the measure just because kids were getting sick!

In the resulting confusion, children with impaired immune systems, who cannot be vaccinated, are staying home from school.

Italy, and much of Europe, was already in the grips of a measles epidemic. 41 000 cases were reported between January and June 2017, up from 24 000 in all of 2018. 37 people have died.

M5S politicians, who previously claimed vaccines were dangerous, have now called for mass vaccinations and for vaccinations to be required to attend schools, although the self certifying is still permitted.

I doubt M5S were that committed to the anti-vaxx cause @mdash; many of its leaders say they had vaccinated their children. So while it is tempting to think that evidence will change an anti-vaxxers mind, it is probably more realistic to view M5S as cynically pandering to a small, vocal group to get votes, and then dropping them when they become a liability. The people injured as a consequence are just collateral damage.